Hermetic Sealing Material

Abstract

Sealing materials for use with membrane supports, and in particular to sealing materials that can be used to form a glassy coating on the exterior surface of a membrane support to prevent gases from entering or exiting the support via the support's exterior walls.

1 . A zinc-alkali-silicate glass consisting essentially of, in mole percent:
 60-70% SiO 2 ;   12-18% ZnO;   6-10% Na 2 O;   6-10% K 2 O;   1-4% ZrO 2 ; and   0.5-2.5% Al 2 O 3 .   
     
     
         2 . A zinc-alkali-silicate glass according to  claim 1 , consisting essentially of, in mole percent:
 62-67% SiO 2 ;   14-16% ZnO;   7-9% Na 2 O;   7-9% K 2 O;   2-4% ZrO 2 ; and   0.5-2% Al 2 O 3 .   
     
     
         3 . A zinc-alkali-silicate glass according to  claim 1 , wherein the glass is substantially free of heavy metals. 
     
     
         4 . A zinc-alkali-silicate glass according to  claim 1 , wherein the glass is substantially free of barium. 
     
     
         5 . A frit blend comprising 40 to 60 weight percent of the zinc-alkali-silicate glass according to claims 1 and 40 to 60 weight percent of inert filler. 
     
     
         6 . The frit blend according to  claim 5  applied to an alumina support, where the CTE of the frit blend matches the CTE of the alumina support within ±10×10 −7 /° C. 
     
     
         7 . The frit blend according to  claim 5 , where the frit blend is substantially free of heavy metals. 
     
     
         8 . A calcium silicoborate glass consisting essentially of, in mole percent:
 30-45% B 2 O 3 ;   25-35% CaO;   23-30% SiO 2 ;   2-6% Al 2 O 3 ; and   1-5% SrO.   
     
     
         9 . A calcium silicoborate glass according to  claim 8 , consisting essentially of, in mole percent:
 36-40% B 2 O 3 ;   27-31% CaO;   24-26% SiO 2 ;   3-5% Al 2 O 3 ; and   1-4% SrO.   
     
     
         10 . A calcium silicoborate glass according to  claim 8 , wherein the glass is substantially free of heavy metals. 
     
     
         11 . A calcium silicoborate glass according to  claim 8 , wherein the glass is substantially free of barium. 
     
     
         12 . A frit blend comprising 75 to 95 weight percent of the calcium silicoborate glass according to claims 1 and 5 to 25 weight percent of inert filler. 
     
     
         13 . The frit blend according to  claim 12  applied to an alumina support, where the CTE of the frit blend matches the CTE of the alumina support within ±10×10 −7 /° C. 
     
     
         14 . The frit blend according to  claim 12 , where the frit blend is substantially free of heavy metals. 
     
     
         15 . A mixed alkali-zinc-phosphate glass consisting essentially of, in mole percent:
 35-50% ZnO;   25-40% P 2 O 5 ;   5-10% Na 2 O;   5-10% K 2 O;   1-5% Li 2 O;   1-5% MoO 3 ;   0.5-4% WO 3 ; and   0.1-4% Al 2 O 3 .   
     
     
         16 . A mixed alkali-zinc-phosphate glass according to  claim 15 , consisting essentially of, in mole percent:
 40-44% ZnO;   31-35% P 2 O 5 ;   7-9% Na 2 O;   6-8% K 2 O;   2-4% Li 2 O;   2-4% MoO 3 ;   1-3% WO 3 ; and   0.5-2% Al 2 O 3 .   
     
     
         17 . A mixed alkali-zinc-phosphate glass according to  claim 15 , wherein the glass is substantially free of heavy metals. 
     
     
         18 . A mixed alkali-zinc-phosphate glass according to  claim 15 , wherein the glass is substantially free of barium. 
     
     
         19 . A frit blend comprising 70 to 95 weight percent of the mixed alkali-zinc-phosphate glass according to  claim 15  and 5 to 30 weight percent inert filler. 
     
     
         20 . The frit blend according to  claim 19  applied to an alumina support, where the CTE of the frit blend matches the CTE of the alumina support within ±10×10 −7 /° C. 
     
     
         21 . The frit blend according to  claim 19 , where the frit blend is substantially free of heavy metals. 
     
     
         22 . A tin-zinc-phosphate glass consisting essentially of, in mole percent:
 40-50% SnO,   25-40% P 2 O 5 , and   15-30% ZnO.   
     
     
         23 . A tin-zinc-phosphate glass according to  claim 22 , consisting essentially of, in mole percent:
 42-46% SnO,   31-35% P 2 O 5 , and   20-24% ZnO.   
     
     
         24 . A tin-zinc-phosphate glass according to  claim 22 , wherein the glass is substantially free of heavy metals. 
     
     
         25 . A tin-zinc-phosphate glass according to  claim 22 , wherein the glass is substantially free of barium. 
     
     
         26 . A frit blend comprising 80 to 100 weight percent of the tin-zinc-phosphate glass according to claims 1 and 0 to 20 weight percent inert filler. 
     
     
         27 . The frit blend according to  claim 26  applied to an alumina support, where the CTE of the frit blend matches the CTE of the alumina support within ±10×10 −7 /° C. 
     
     
         28 . The frit blend according to  claim 26 , where the frit blend is substantially free of heavy metals.